Commit 1b4d2a0b authored by Zhang Yi's avatar Zhang Yi Committed by Theodore Ts'o
Browse files

ext4: check env when mapping and modifying extents 



Add ext4_check_map_extents_env() to the places where loading extents,
mapping blocks, removing blocks, and modifying extents, excluding the
I/O writeback context. This function will verify whether the locking
mechanisms in place are adequate.

Suggested-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarZhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250423085257.122685-9-yi.zhang@huaweicloud.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 7871da20

fs/ext4/extents.c

+6 −0
Original line number Diff line number Diff line
@@ -611,6 +611,8 @@ int ext4_ext_precache(struct inode *inode) 
	if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))

		return 0;	/* not an extent-mapped inode */



	ext4_check_map_extents_env(inode);



	down_read(&ei->i_data_sem);

	depth = ext_depth(inode);
@@ -5342,6 +5344,8 @@ static int ext4_collapse_range(struct file *file, loff_t offset, loff_t len) 
	start_lblk = offset >> inode->i_blkbits;

	end_lblk = (offset + len) >> inode->i_blkbits;



	ext4_check_map_extents_env(inode);



	down_write(&EXT4_I(inode)->i_data_sem);

	ext4_discard_preallocations(inode);

	ext4_es_remove_extent(inode, start_lblk, EXT_MAX_BLOCKS - start_lblk);
@@ -5443,6 +5447,8 @@ static int ext4_insert_range(struct file *file, loff_t offset, loff_t len) 
	start_lblk = offset >> inode->i_blkbits;

	len_lblk = len >> inode->i_blkbits;



	ext4_check_map_extents_env(inode);



	down_write(&EXT4_I(inode)->i_data_sem);

	ext4_discard_preallocations(inode);

fs/ext4/inode.c

+10 −3
Original line number Diff line number Diff line
@@ -650,11 +650,14 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, 
		return -EFSCORRUPTED;



	/*

	 * Do not allow caching of unrelated ranges of extents during I/O

	 * submission.

	 * Callers from the context of data submission are the only exceptions

	 * for regular files that do not hold the i_rwsem or invalidate_lock.

	 * However, caching unrelated ranges is not permitted.

	 */

	if (flags & EXT4_GET_BLOCKS_IO_SUBMIT)

		WARN_ON_ONCE(!(flags & EXT4_EX_NOCACHE));

	else

		ext4_check_map_extents_env(inode);



	/* Lookup extent status tree firstly */

	if (!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) &&
@@ -1801,6 +1804,8 @@ static int ext4_da_map_blocks(struct inode *inode, struct ext4_map_blocks *map) 
	ext_debug(inode, "max_blocks %u, logical block %lu\n", map->m_len,

		  (unsigned long) map->m_lblk);



	ext4_check_map_extents_env(inode);



	/* Lookup extent status tree firstly */

	if (ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) {

		map->m_len = min_t(unsigned int, map->m_len,
@@ -4113,6 +4118,7 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length) 
		ext4_lblk_t hole_len = end_lblk - start_lblk;



		ext4_fc_track_inode(handle, inode);

		ext4_check_map_extents_env(inode);

		down_write(&EXT4_I(inode)->i_data_sem);

		ext4_discard_preallocations(inode);
@@ -4266,8 +4272,9 @@ int ext4_truncate(struct inode *inode) 
		goto out_stop;



	ext4_fc_track_inode(handle, inode);

	down_write(&EXT4_I(inode)->i_data_sem);

	ext4_check_map_extents_env(inode);



	down_write(&EXT4_I(inode)->i_data_sem);

	ext4_discard_preallocations(inode);



	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))